In general, as the size of a liquid crystal display of a cellular phone (mobile communication terminal), such as a smart phone and a tablet PC, increases, various forms of cellular phone cases are manufactured in order to protect a screen and an exterior of the cellular phone by being mounted on the corresponding cellular phone.
Among them, representatively, a wallet form of cellular phone case is most widely used, which is made of leather or artificial leather to cover front and rear surfaces and one surface of a corresponding cellular phone, and expose a screen of the corresponding cellular phone while a front surface part is selectively opened and closed.
However, since the aforementioned cellular phone case in the related art does not have a separate function which interworks with the cellular phone in addition to protecting the screen and the exterior of the cellular phone and providing an aesthetic design, there is a limit in providing additional conveniences to a user through the cellular phone case.
Thus, the convenience of the user may be significantly increased if a function to operate the smart phone in link with the cellular phone case is added to the protective cellular phone case.